Manifold for collimating light

Abstract

The present disclosure provides systems, methods and apparatus to collimate light. In one aspect, a manifold to collimate light can be used to illuminate a display or project an image. The manifold can be formed of optically transmissive material and can have a backside for receiving light from a light source and a front wall, opposite the backside, for outputting collimated light. The front wall can include a plurality of lens. The upper and bottom walls of the manifold can extend along a curve from the backside to the front wall. The manifold can be hollowed, with an internal cavity that opens to the backside. The manifold can be configured to collimate light propagating in directions extending out of a plane, while light propagating from the light source in directions within the plane is not collimated or is less collimated.

1 . A manifold system for collimating light, comprising:
 an elongated manifold body of optically-transmissive material, the body comprising:
 a backside configured to receive light from a light source; 
 a front wall opposite the backside and configured to output light from the light source; 
 a curved upper wall extending from the backside to the front wall; 
 a curved lower wall extending from the backside to the front wall; and 
   a plurality of lens on the front wall of the body,   wherein the body is configured to output light in a plane defined by a first axis extending horizontally along a length of the front wall and a second axis extending from the backside to the front wall of the body, wherein the light has a relatively narrow angular distribution on axes out of the plane and a relatively wide angular distribution in the plane.   
     
     
         2 . The system of  claim 1 , wherein the elongated body has a hollow internal volume opening to a hole on the backside. 
     
     
         3 . The system of  claim 2 , wherein a ratio of a width of the front wall to a width of the hole is about 2:1 or less. 
     
     
         4 . The system of  claim 1 , wherein a side of the front wall opposite the lens is curved. 
     
     
         5 . The system of  claim 4 , wherein the side of the front wall opposite the lens has a convex or concave shape. 
     
     
         6 . The system of  claim 1 , wherein the upper wall extends along a Bezier curve from the backside to the front wall. 
     
     
         7 . The system of  claim 6 , wherein the lower wall extends along a Bezier curve from the backside to the front wall. 
     
     
         8 . The system of  claim 1 , wherein the upper and lower walls are each coated with a reflective material. 
     
     
         9 . The system of  claim 1 , further comprising the light source in optical communication with the backside, wherein the light source is a light emitting diode. 
     
     
         10 . The system of  claim 1 , wherein the front wall is configured to output light from the light source to an optically-transmissive panel. 
     
     
         11 . The system of  claim 10 , wherein the optically-transmissive panel comprises light turning features configured to turn light propagating inside the panel such that the light propagates out of a major surface of the panel. 
     
     
         12 . The system of  claim 11  wherein the light turning features comprise facets having curved corners. 
     
     
         13 . The system of  claim 11 , further comprising a display having a major display surface facing the major surface of the panel. 
     
     
         14 . The system of  claim 13 , wherein the display comprises display elements formed of interferometric modulators. 
     
     
         15 . The system of  claim 1 , wherein the lens are an integral part of the front wall. 
     
     
         16 . The system of  claim 1 , wherein the manifold body is disposed in a pico-projector. 
     
     
         17 . The system of  claim 16 , wherein the manifold body and the light source are configured to provide light for projecting images from the pico-projector. 
     
     
         18 . The system of  claim 1 , further comprising:
 a display;   a processor that is configured to communicate with the display, the processor being configured to process image data; and   a memory device that is configured to communicate with the processor.   
     
     
         19 . The apparatus of  claim 18 , further comprising:
 a driver circuit configured to send at least one signal to the display.   
     
     
         20 . The apparatus of  claim 19 , further comprising:
 a controller configured to send at least a portion of the image data to the driver circuit.   
     
     
         21 . The apparatus of  claim 18 , further comprising:
 an image source module configured to send the image data to the processor.   
     
     
         22 . The apparatus of  claim 21 , wherein the image source module comprises at least one of a receiver, transceiver, and transmitter. 
     
     
         23 . The apparatus of  claim 18 , further comprising:
 an input device configured to receive input data and to communicate the input data to the processor.   
     
     
         24 . A display device, comprising:
 an image formation means for forming elements of a displayed image;   a light generating means for generating light;   a light turning means for redirecting light generated by the light generating means towards the image formation means; and   a collimating means for collimating light generated by light generating means and injecting the collimated light into the light turning means.   
     
     
         25 . The device of  claim 24 , wherein the image formation means comprises interferometric modulators. 
     
     
         26 . The device of  claim 24 , wherein the light generating means comprises a light emitting diode. 
     
     
         27 . The device of  claim 24 , wherein the light turning means comprises a panel of optically transmissive material, the panel comprising a plurality of light turning features configured to redirect light, propagating through the panel, out of the panel towards the image formation means. 
     
     
         28 . The device of  claim 27 , wherein the light turning features comprise facets. 
     
     
         29 . The device of  claim 28 , wherein the facets have rounded corners. 
     
     
         30 . The device of  claim 24 , wherein the collimating means comprises:
 an elongated manifold body of optically-transmissive material, the body comprising:
 a backside configured to receive light from the light generating means; 
 a front wall opposite the backside and configured to output light from the light generating means to the light turning means; 
 a curved upper wall extending from the backside to the front wall; 
 a curved lower wall extending from the backside to the front wall; and 
 a plurality of lens on the front wall of the body. 
   
     
     
         31 . The device of  claim 30 , wherein the collimating means is configured to output light in a plane defined by a first axis extending horizontally along a length of the front wall and a second axis extending from the backside to the front wall of the body, wherein the light has a relatively narrow angular distribution on axes out of the plane and a relatively wide angular distribution in the plane. 
     
     
         32 . A method for manufacturing a display device, comprising:
 providing a light guide panel;   providing a light source; and   providing a light collimating manifold between the light source and the light guide panel, wherein the light collimating manifold is configured to output light from the light source in a relatively narrow angular distribution out of a plane of the light guide panel and a relatively wide angular distribution in the plane of the light guide panel.   
     
     
         33 . The method of  claim 32 , wherein the light collimating manifold comprises:
 an elongated manifold body of optically-transmissive material, the manifold body comprising:
 a backside configured to receive light from the light source; 
 a front wall opposite the backside and configured to output light from the light source to the light guide panel; 
 a curved upper wall extending from the backside to the front wall; 
 a curved lower wall extending from the backside to the front wall; and 
 a plurality of lens on the front wall of the manifold body. 
   
     
     
         34 . The method of  claim 33 , further comprising hollowing out the manifold body to define a manifold body internal cavity opening to the backside. 
     
     
         35 . The method of  claim 32 , wherein providing the light guide panel comprises defining a plurality of facets in an optically transmissive panel, the optically transmissive panel forming the light guide panel. 
     
     
         36 . The method of  claim 32 , further comprising providing a display disposed under the light guide panel. 
     
     
         37 . The method of  claim 36 , wherein the display comprises a plurality of interferometric modulators, the interferometric modulators forming pixels of the display.